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Valliappan, Valliappan (author), Remmers, J. J.C. (author), Barnhoorn, A. (author), Smeulders, D.M.J. (author)
In this paper, we present a two-dimensional numerical model for modelling of hydraulic fracturing in anisotropic media. The numerical model is based on extended finite element method. The saturated porous medium is modelled using Biot’s theory of poroelasticity. An enhanced local pressure model is used for modelling the pressure within the...
journal article 2017
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Drijver, Margriet (author), Hermans, M.H. (author), Smeulders, Tom (author), Spek, Emile (author)
Woningcorporaties zijn in belangrijke mate afhankelijk van externe partijen bij het uitvoeren van hun taken.<br/>Een gemiddelde woningcorporatie werkt met tientallen verschillende opdrachtnemers. Die worden bijvoorbeeld ingeschakeld voor onderhoud, nieuwbouw en beheer, maar ook voor ICT-taken, accountancy, juridisch advies en andere vormen van...
report 2017
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Zhubayev, A. (author), Houben, M.E. (author), Smeulders, D.M.J. (author), Barnhoorn, A. (author)
We have conducted ultrasonic experiments, between 0.3 and 1 MHz, to measure velocity and attenuation (Q?1) anisotropy of P- and S-waves in dry Whitby Mudstone samples as a function of stress. We found the degree of anisotropy to be as large as 70% for velocity and attenuation. The sensitivity of P-wave anisotropy change with applied stress is...
journal article 2015
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Barnhoorn, A. (author), Zhubayev, A. (author), Houben, M. (author), Hardebol, N.J. (author), Smeulders, D.M.J. (author)
journal article 2015
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Fan, H. (author), Smeulders, D.M.J. (author)
Borehole waves are strongly affected by adjacent porous zones or by fractures intersecting the borehole. A theoretical description for both porous and fracture zones is possible based on the introduction of an effective borehole fluid bulk modulus, characterizing the wave attenuation via borehole wall impedance. This impedance can be calculated...
journal article 2013
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Grobbe, N. (author), Schoemaker, F.C. (author), Schakel, M.D. (author), De Ridder, S.A.L. (author), Slob, E.C. (author), Smeulders, D.M.J. (author)
conference paper 2012
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Fan, H. (author), Smeulders, D.M.J. (author)
journal article 2012
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Schoemaker, E.C. (author), Grobbe, N. (author), Schakel, M.D. (author), De Ridder, S.A.L. (author), Slob, E.C. (author), Smeulders, D.M.J. (author)
We experimentally validate a relatively recent electrokinetic formulation of the streaming potential (SP) coefficient as developed by Pride (1994). The start of our investigation focuses on the streaming potential coefficient, which gives rise to the coupling of mechanical and electromagnetic fields. It is found that the theoretical amplitude...
journal article 2012
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Van Dalen, K.N. (author), Drijkoningen, G.G. (author), Smeulders, D.M.J. (author), Heller, H.K.J. (author), Glorieux, C. (author), Sarens, B. (author), Verstraeten, B. (author)
The interface-wave impedance and ellipticity are wave attributes that interrelate the full waveforms as observed in different components. For each of the fluid/elastic-solid interface waves, i.e., the pseudo-Rayleigh (pR) and Stoneley (St) waves, the impedance and ellipticity are found to have different functional dependencies on Young’s modulus...
journal article 2011
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Schakel, M.D. (author), Smeulders, D.M.J. (author), Slob, E.C. (author), Heller, H.K.J. (author)
Coupled seismic and electromagnetic (EM) wave effects in fluid-saturated porous media are measured since decades. However, direct comparisons between theoretical seismoelectric wavefields and measurements are scarce. A seismoelectric full-waveform numerical model is developed, which predicts both the fluid pressure and the electric wavefields in...
journal article 2011
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Fan, H. (author), Smeulders, D.M. (author)
We perform wave experiments using a vertical shock tube setup. Shock waves are generated by the rupture of a thin membrane. In the test section, the incident pressure waves generate borehole-guided waves along water-saturated samples. The tube is equipped with side wall gages and a mobile pressure probe, so that the attenuation and reflection of...
journal article 2011
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Schakel, M.D. (author), Smeulders, D.M.J. (author), Slob, E.C. (author), Heller, H.K.J. (author)
Understanding the seismoelectric interface response is important for developing seismoelectric field methods for oil exploration and environmental/engineering geophysics. The existing seismoelectric theory has never been validated systematically by controlled experiments. We have designed and developed an experimental setup in which acoustic-to...
journal article 2011
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Van Dalen, K.N. (author), Drijkoningen, G.G. (author), Smeulders, D.M.J. (author)
At the fluid/porous-medium interface the pseudo-Rayleigh (pR) and pseudo-Stoneley (pSt) waves exist. The relation with the corresponding poles in the slowness plane is not unambiguous, depending on the choice of branch cuts. For a point-force excitation, the far-field Green’s functions are computed using vertical branch cuts (method I) implying...
journal article 2011
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Schakel, M.D. (author), Smeulders, D.M.J. (author), Slob, E.C. (author), Heller, H.K.J. (author)
A full-waveform seismoelectric numerical model incorporating the directivity pattern of a pressure source is developed. This model provides predictions of coseismic electric fields and the electromagnetic waves that originate from a fluid/porous-medium interface. An experimental setup in which coseismic electric fields and interface responses...
journal article 2011
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Vogelaar, B. (author), Smeulders, D.M.J. (author), Harris, J. (author)
Seismic effects of a partially gas-saturated subsurface have been known for many years. For example, patches of nonuniform saturation occur at the gas-oil and gas-water contacts in hydrocarbon reservoirs. Open-pore boundary conditions are applied to the quasi-static Biot equations of poroelasticity to derive an exact analytic expression of the...
journal article 2010
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Van Dalen, K.N. (author), Ghose, R. (author), Drijkoningen, C.G. (author), Smeulders, D.M.J. (author)
A reliable estimate of the in?situ permeability of a porous layer in the subsurface is extremely difficult to obtain. We have observed that at the field seismic frequency band the poroelastic behavior for different seismic wavetypes can differ in such a way that their combination gives unique estimates of in?situ permeability and porosity...
journal article 2010
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Van Dalen, K.N. (author), Drijkoningen, G.G. (author), Smeulders, D.M.J. (author)
Pseudo interface waves can exist at the interface of a fluid and a fluid-saturated poroelastic solid. These waves are typically related to the pseudo-Rayleigh pole and the pseudo-Stoneley pole in the complex slowness plane. It is found that each of these two poles can contribute (as a residue) to a full transient wave motion when the...
journal article 2010
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Schakel, M.D. (author), Smeulders, D. (author)
The dispersion relation for seismoelectric wave propagation in poroelastic media is formulated in terms of effective densities comprising all viscous and electrokinetic coupling effects. Using Helmholtz decomposition, two seismoelectric conversion coefficients are derived, for an incident P-wave upon an interface between a compressible fluid and...
journal article 2010
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Wisse, C.J. (author), Smeulders, D.M.J. (author), Chao, G. (author), Van Dongen, M.E.H. (author)
The classical theory of wave propagation in elastic cylinders is extended to poro-elastic mandrel modes. The classical theory predicts the existence of undamped L modes and damped C, I, and Z modes. These waves also appear in poro-elastic mandrels, but all of them become damped because of viscous effects. The presence of the Biot slow bulk wave...
journal article 2007
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Chao, G.E. (author), Smeulders, D.M.J. (author), Van Dongen, M.E.H. (author)
We present an exact theory of attenuation and dispersion of borehole Stoneley waves propagating along porous rocks containing spherical gas bubbles by using the Biot theory. An effective frequency-dependent fluid bulk modulus is introduced to describe the dynamic (oscillatory) behavior of the gas bubbles. The model includes viscous, thermal, and...
journal article 2007
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